The section in the act is pretty specific on listing what a serious risk is in my mind (the only clarification would be that risk could have cause a notifiable injury in other circumstances) - what I seem to see the struggle with is what is considered "unplanned or uncontrolled" and "immediate or imminent". My go to question would be to ask "was there any physical controls stopping a person from being hurt, or did we not hurt anyone just because of pure luck.
Example being if during a crane lift you drop a load - if the only control that stopped anyone from being underneath the load was a site/company "golden rule" to not walk under suspended loads then I would still consider that a notifiable incident, However if the area had been cordoned off and access to underneath the load was restricted (even just by warning/danger tape) then I would lean towards it being planned/controlled which removes the immediate/imminent risk.

In my experience I have had this actual incident occur. When I spoke to worksafe all they were concerned about was if there was actually anyone in the vicinity in immediate or imminent danger. They did not discuss barriers or any other control that was in place. When I described the scene, and the closest person they were comfortable and I was not required to report.

@Joanne Brown Agreed. It has always been my opinion that it is better to have a chat with WorkSafe and get a consensus if notification is required or not. I believe when Worksafe see a company being proactive, it creates a better working relationship.

'planned' means that the drop was intentional. i.e. did the operator deliberately drop the load, and was everyone aware that it was going to happen.
As an example - a helicopter carrying out lifting operations. If hte load was dropped in the appropriate place, in accordance with a plan, then no reporting. If the pilot had to release the load en-route for some reason, even if well away from people, then it needs to be reported.

planned could also include contingency/emergency planning - if the load happens to be dropped we are sure it would not be a risk to anyone as our plan had excluded everyone from anywhere it could drop.

To add some context to this, this has been requested by one of our customers who frequently have fuel spills on their sites which can range from a few drops to 100s of litres. We are tasked with cleaning these up nationwide. These are a regular occurring (around ten per month) and they want us to access these as to whether WorkSafe notification is required, for us this poses an issue as we would want to have nationwide consistency.

In my experience, if there is any doubt then report it. I can't think of a single case where someone has got into trouble for reporting a non notifiable incident, but plenty of examples when they haven't.

In terms of planned vs unplanned, Worksafe explain further by including the following in their guidance....

Notifiable incidents do not include controlled activities that form part of the business or undertaking (eg the controlled release of water from a dam).

The crane example given earlier in the thread would, in my book, be notifiable ("the fall or release from height of any plant, substance, or thing").

With regards to the fuel spill, I guess it would depend on where these are occurring and whether they are mitigated, for example, small spills captured by bunds or drip trays being placed under decanting areas vs the failure of a fuel line/accessory.

The Worksafe guidance says:
"A notifiable incident is an unplanned or uncontrolled incident in relation to a
workplace that exposes the health and safety of workers or others to a serious risk
arising from immediate or imminent exposure to:
–– a substance escaping, spilling, or leaking"
from: https://worksafe.govt.nz/dmsdocument/833-what-events-need-to-be-notified

So, if the spill is large enough that they're calling in outside specialists to clean it up, then I would think that it needs notification.
But, as others have said, its better, and fairly easy, to get clarification directly from Worksafe (in writing preferably!)

This was the WorkSafe response:

WorkSafe does not interpret the Health and Safety at Work Act 2015, we cannot provide legal or specific advice. We can provide relevant guidance.

We have a guidance criteria for notifiable events, however this does not define serious risk or have set measures for incidents as the situation can vary depending on the scenario. Please see the following link for the guide:

https://worksafe.govt.nz/notifications/notifiable-event/what-is-a-notifiable-event/#lf-doc-39637

In closing, if you are wishing to report an incident and are unsure if it is notifiable to WorkSafe, please call 0800 030 040. Alternatively, for a legal interpretation, you may also wish to consider independent legal advice specific to your position.

...get clarification directly from WorkSafe (in writing preferably!) — Aaron Marshall

Good luck with that! (as Chris has just experienced!)

It is interesting that you client is putting the burden on a contractor to make the decision to notify or not and/or are not being involved in making the decision on what should be notifiable or not.
To be clear it is the PCBU who managers or controls the workplace that has the duty to prevent the scene of a notifiable event from being disturbed, and the PCBU who's conduct resulted in the notifiable event to notify WorkSafe - I would be making this clear to the client.

My suggestion to the client would be to put a process in place where any significant spill of fuel occurs is that they call you, then they call WorkSafe and let them know what fuel was spilled, approximately how much, that the spill containment team have been called out to minimize the risk and to request that the site can be released once the clean up is completed.

As for what is a significant spill, I would look at other parts of the hazardous substances legislation that deal with emergency management of spills - such as for petrol it could be 50 L (being the volume over which a hazardous substance location would be required if it was the only hazardous substance on the site and it was being stored/use in open containers).

Once you come to some agreement on the process and definition I would run it past a lawyer to check...

Thanks for that Matt. That's really helpful

The one time I've had to ask regarding whether an event was notifiable or not, they did give clear-cut advice that it didn't need to be notified.

Regarding the HSNO spill reporting, I've seen a company policy that states an area (in square metres) for the size of spill required to be reported. It's easier for someone to estimate the size of a puddle on the ground than the volume.

My main concern here though is that they seem to be recurring spills that are accepted.

True that they are good at letting you know if they consider a specific case notifiable or not, I was more talking about their input prior to try and determine any sort of threshold for notifying.

But that raises a good point - once you start notifying these "grey" areas cases, keep a good record then review that periodically to refine what does/doesn't need to be notified. That will give you a much better case in the off chance you get pinged for not notifying something that in the past they told you didn't need to be notified.

I am guessing that these situation may be the kind similar to (or actually) a petrol station forecourt... untrained operators (the public) accidentally spilling fuel from a pump.

The situation I noted was similar to a petrol station; an aircraft ramp where refuelling with avgas was taking place.

It is a petrol station forecourt, generally members of the public and the sites may be manned or unmanned.

This thread makes a very good case for proactively developing relationships with WorkSafe inspectors, who are familiar with the work you are doing, and also get a clear sense of your organisation's culture and commitment. It can be very useful to have someone on your side in a moment of need, especially if a time comes where you are not sure what to do, and they can see you are taking steps to do everything that is 'reasonably practicable' in response to events.

Having said that, WorkSafe will always avoid taking a legal position because their main role is to advise and support enforcement.

As has already been suggested, it is also always a very good idea to document all correspondence. As much as I hate the 'cover your butt' approach, we still live in a country with a legal framework and culture that may require this.